[PATCH 6/8] drm/vram-helper: don't use ttm bo->offset v3

[Gerd Hoffmann]

On Thu, Mar 05, 2020 at 02:29:08PM +0100, Nirmoy Das wrote:
> Calculate GEM VRAM bo's offset within vram-helper without depending on
> bo->offset.
> 
> Signed-off-by: Nirmoy Das <nirmoy.das at amd.com>
> Reviewed-by: Daniel Vetter <daniel.vetter at ffwll.ch>
> ---
>  drivers/gpu/drm/drm_gem_vram_helper.c | 9 ++++++++-
>  1 file changed, 8 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/drm_gem_vram_helper.c b/drivers/gpu/drm/drm_gem_vram_helper.c
> index 92a11bb42365..2749c2d25ac4 100644
> --- a/drivers/gpu/drm/drm_gem_vram_helper.c
> +++ b/drivers/gpu/drm/drm_gem_vram_helper.c
> @@ -198,6 +198,13 @@ u64 drm_gem_vram_mmap_offset(struct drm_gem_vram_object *gbo)
>  }
>  EXPORT_SYMBOL(drm_gem_vram_mmap_offset);
> 
> +static s64 drm_gem_vram_pg_offset(struct drm_gem_vram_object *gbo)
> +{
> +	if (WARN_ON_ONCE(!gbo->bo.mem.mm_node))
> +		return 0;

returns 0 on error.

> +	return gbo->bo.mem.start;
> +}
> +
>  /**
>   * drm_gem_vram_offset() - \
>  	Returns a GEM VRAM object's offset in video memory
> @@ -214,7 +221,7 @@ s64 drm_gem_vram_offset(struct drm_gem_vram_object *gbo)
>  {
>  	if (WARN_ON_ONCE(!gbo->pin_count))
>  		return (s64)-ENODEV;

returns -errno on error.

> -	return gbo->bo.offset;
> +	return drm_gem_vram_pg_offset(gbo) << PAGE_SHIFT;

And given that one calls the other behavior on error should better be
consistent ...

cheers,
  Gerd